Abstract: An OFDMA communication system is provided that schedules partial usage of subchannels (PUSC) major groups by assigning a beam matrix of a plurality of beam matrices to each major group of multiple PUSC major groups, receiving an uplink signal from each user equipment of multiple users equipment, which uplink signal provides an indication of a channel response associated with the user equipment, determining, for each user equipment of the multiple users equipment and based on the indication of channel quality received from the user equipment, a beam matrix and major group to which to assign the user equipment, and based on the determination of a beam matrix and major group to which to assign each user equipment of the multiple users equipment, assigning two or more users equipment of the multiple users equipment to a same beam matrix and major group during a same time slot.

Abstract: Disclosed are a wireless communication system, method, and site controller for mitigating at least one of a transmission timing synchronization loss and a receiving timing synchronization loss at a base station. The method includes determining, at a first base station, a loss of a timing reference the timing reference is used by the first base station for timing synchronization of at least one of a transmission and reception of wireless data. The timing synchronization is predefined and common between at least the first base station and a second base station. The method further includes adjusting, in response to the determining, at least one of a transmit guard time and a receive guard time by at least one symbol time.

Abstract: A method, a system and a receiver device provide timing and frequency correction in a spatial division multiple access (SDMA) system. A timing and frequency correction (TFC) logic/utility obtains a timing error estimate by using pilot symbols on a slot of six tiles. The TFC logic estimates the timing error based on pilot phase differences between unique pairs of tiles when the frequency separation of the tiles is less than a threshold value. When none of the unique pairs of tiles satisfies the threshold value, the TFC logic estimates timing error based on an exhaustive search for each candidate phase error value. The TFC logic performs timing error correction via a timing error estimate based on pilots from the symbols received on each antenna. The TFC logic performs inexplicit frequency error correction according to phase differences based on relative symbol indices.

Abstract: An OFDMA communication system is provided that schedules partial usage of subchannels (PUSC) major groups by assigning a beam matrix of a plurality of beam matrices to each major group of multiple PUSC major groups, receiving an uplink signal from each user equipment of multiple users equipment, which uplink signal provides an indication of a channel response associated with the user equipment, determining, for each user equipment of the multiple users equipment and based on the indication of channel quality received from the user equipment, a beam matrix and major group to which to assign the user equipment, and based on the determination of a beam matrix and major group to which to assign each user equipment of the multiple users equipment, assigning two or more users equipment of the multiple users equipment to a same beam matrix and major group during a same time slot.

Abstract: A wireless communication system (100), method, and site controller (112) schedule at least one of transmission and reception of wireless data by at least one wireless communication device. A distance is determined between at least one wireless communication device (104) and a base station (108) in a wireless communication cell (402). At least one of a downlink subframe (610) and an uplink subframe (614) of a time division duplexing frame (602) is segmented into a plurality of segments. The at least one wireless communication device (104) is scheduled into at least one of the plurality of segments of the downlink subframe (610) and the uplink subframe (614) based on the distance determined between the at least one wireless communication device (104) and the base station (108).

Abstract: A method, a system and a receiver device provide timing and frequency correction in a spatial division multiple access (SDMA) system. A timing and frequency correction (TFC) logic/utility obtains a timing error estimate by using pilot symbols on a slot of six tiles. The TFC logic estimates the timing error based on pilot phase differences between unique pairs of tiles when the frequency separation of the tiles is less than a threshold value. When none of the unique pairs of tiles satisfies the threshold value, the TFC logic estimates timing error based on an exhaustive search for each candidate phase error value. The TFC logic performs timing error correction via a timing error estimate based on pilots from the symbols received on each antenna. The TFC logic performs inexplicit frequency error correction according to phase differences based on relative symbol indices.

Abstract: A communication device is provided that is capable of operating in an OFDM or communication system and that provides for cancellation of in-band spurs. The communication device identifies a bin of multiple bins associated with an output of an inverse transformer and comprising a spur and estimates one or more spur phase parameters and a spur amplitude in association with the identified bin. In one embodiment of the present invention, the one or more spur phase parameters includes a spur initial phase and a spur change rate. When the communication device receives a signal from another communication device, the communication device transforms the received signal to produce a multiple parallel output signals that are each associated with a bin of the multiple bins and cancels a spur in an output signal associated with the identified bin based on the estimated one or more spur phase parameters and spur amplitude.

Abstract: An apparatus and method for uplink synchronization without periodic ranging in a communication system includes a first step (700) of detecting embedded pilot signals in data traffic from mobile stations. A next step (702) includes estimating a time error by calculating a pilot signal phase difference across a tone index within the same OFDM symbol. A next step (704) includes estimating a frequency error by calculating a pilot signal phase difference across multiple OFDM symbols within a tone. A next step (706) includes determining if at least one of the estimated time and frequency errors exceed a predetermined threshold. A next step (708) includes sending synchronization information to at least one mobile station for the mobile station to synchronize (710) its transmit signals in response to at least one of the time and frequency error.

Abstract: A method for selecting at least one operating parameter of a communication system (100). The method can include determining a receive signal strength indicator (RSSI) for a communication signal (330). An intermediate value (D) for the communication signal can be determined based on, at least in part, a received value (ri) of at least one known datum, a predetermined value (pi) of the known datum and a channel estimate ({tilde over (h)}i). Further, a carrier to interference and noise ratio (CINR) can be estimated based on, at least in part, the RSSI and the intermediate value. The operating parameter can be selected based on, at least in part, the estimated CINR.

Abstract: Arrangements relating to an Orthogonal Frequency Division Multiplexing (OFDM) receiver (200) can include performing at least one Low-Density Parity Check (LDPC) decoding attempt on a received signal (725) and evaluating at least one parity check for each LDPC decoding attempt (735). Failed LDPC decoding attempts can be counted according to the evaluated parity checks (740). The signal can be selectively processed through at least one joint demodulation-decoding loop according to the counting of failed LDPC decoding attempts (745).

Abstract: A wireless communication system (100), method, and site controller (112) schedule at least one of transmission and reception of wireless data by at least one wireless communication device. A distance is determined between at least one wireless communication device (104) and a base station (108) in a wireless communication cell (402). At least one of a downlink subframe (610) and an uplink subframe (614) of a time division duplexing frame (602) is segmented into a plurality of segments. The at least one wireless communication device (104) is scheduled into at least one of the plurality of segments of the downlink subframe (610) and the uplink subframe (614) based on the distance determined between the at least one wireless communication device (104) and the base station (108).

Abstract: A communication device is provided that is capable of operating in an OFDM or communication system and that provides for cancellation of in-band spurs. The communication device identifies a bin of multiple bins associated with an output of an inverse transformer and comprising a spur and estimates one or more spur phase parameters and a spur amplitude in association with the identified bin. In one embodiment of the present invention, the one or more spur phase parameters includes a spur initial phase and a spur change rate. When the communication device receives a signal from another communication device, the communication device transforms the received signal to produce a multiple parallel output signals that are each associated with a bin of the multiple bins and cancels a spur in an output signal associated with the identified bin based on the estimated one or more spur phase parameters and spur amplitude.

Abstract: Disclosed are a wireless communication system, method, and site controller for mitigating at least one of a transmission timing synchronization loss and a receiving timing synchronization loss at a base station. The method includes determining, at a first base station, a loss of a timing reference the timing reference is used by the first base station for timing synchronization of at least one of a transmission and reception of wireless data. The timing synchronization is predefined and common between at least the first base station and a second base station. The method further includes adjusting, in response to the determining, at least one of a transmit guard time and a receive guard time by at least one symbol time.

Abstract: An access point (108) in a dual-frequency TDD communication system (100) includes a transceiver (122) that transmits information to a first group of subscriber devices (104a-n) at a first frequency (f1) and contemporaneously receives information from a second group of a subscriber devices (106a-n) at a second frequency (f2) during at least a portion of a period of time (T1). The access point (108) also transmits information to the second group of subscriber devices (106a-n) at the second frequency (f2) and contemporaneously receives information from the first group of subscriber devices (104a-n) at the first frequency (f1) during at least a portion of a second period of time (T3). A method for performing a dual-frequency communication scheme is also provided.

Abstract: A method for selecting at least one operating parameter of a communication system (100). The method can include determining a receive signal strength indicator (RSSI) for a communication signal (330). An intermediate value (D) for the communication signal can be determined based on, at least in part, a received value (ri) of at least one known datum, a predetermined value (pi) of the known datum and a channel estimate ({tilde over (h)}i). Further, a carrier to interference and noise ratio (CINR) can be estimated based on, at least in part, the RSSI and the intermediate value. The operating parameter can be selected based on, at least in part, the estimated CINR.

Abstract: An apparatus (100) and method dynamically allocates radio frequency receive path resources as required by a programmable location engine (112). The programmable location engine (112) employs cascaded time of arrival and direction of arrival algorithms to determine per remote unit location data. The apparatus (100) employs a phased array antenna (104) and a programmable receiver switching apparatus (108). A plurality of radio frequency receivers (102a-102n) receive a plurality of different carriers, such as CDMA carriers, on each of a different phased array antenna element (106a-106d).

Abstract: A digital receiver (200) and transmitter (300), wherein the digital receiver includes a plurality of antennas (202) for receiving uplink radio frequency signals; a plurality of analog to digital converters (210) for converting the received radio frequency signals into digital signals; a switched digital down converter (214) for down converting one of the digital signals to a baseband IF signal; and a channel processor (228) for recovering one of a plurality of communication channels contained within the baseband IF signal.

Abstract: A multiple access digital up converter/modulator includes selectors (1606, 1608) having inputs (1602, 1604) and outputs coupled to first and second interpolating filters (1610, 1626). The output of the first interpolating filter is selectively coupled to a first mixer (1612) and a first adder (1622), the first adder also receiving a first phase value and the output is coupled to a first phase accumulator (1616) the output of which is coupled to a first sinusoid generator (1614) and selectively coupled to a second sinusoid generator (1630). The output of each of the first and second mixers are selectively coupled to an output adder (1634) and to inputs of the first and second mixers. The output of the second interpolating filter (1626) is selectively coupled to a second mixer (1628) and a second adder (1638), which also receives a second phase value and the output of which is coupled to a second phase accumulator (1640) the output of which is selectively coupled to the second sinusoid generator.

Abstract: A multi-channel digital transceiver (400) receives uplink radio frequency signals and converts these signals to digital intermediate frequency signals. Digital signal processing, including a digital converter module (426), is employed to select digital intermediate frequency signals received at a plurality of antennas (412) and to convert these signals to baseband signals. The baseband signals are processed to recover a communication channel therefrom. Downlink baseband signals are also processed and digital signal processing within the digital converter module (426) up converters and modulates the downlink baseband signals to digital intermediate frequency signals. The digital intermediate frequency signals are converted to analog radio frequency signals, amplified and radiated from transmit antennas (420).

Abstract: A multi-channel digital transceiver (400) receives uplink radio frequency signals and converts these signals to digital intermediate frequency signals. Digital signal processing, including a digital converter module (426), is employed to select digital intermediate frequency signals received at a plurality of antennas (412) and to convert these signals to baseband signals. The baseband signals are processed to recover a communication channel therefrom. Downlink baseband signals are also processed and digital signal processing within the digital converter module (426) up converters and modulates the downlink baseband signals to digital intermediate frequency signals. The digital intermediate frequency signals are converted to analog radio frequency signals, amplified and radiated from transmit antennas (420).